The present invention concerns a device for stretching muff-sewn hides, particularly for manufacturing furs and the like.
For stretching, or drawing, hides for furs a method is presently known wherein the longitudinal edges of two overlapped hides are sewn and the resulting hide muff is then put on a substantially V-shaped frame having two strips with ends connected to leverages capable to be straddled by means of a threaded, hand driven rod. This frame presents various drawbacks and disadvantages, the most remarkable ones being the impossibility to stretch the hides in the middle of their ends, i.e. head side and tail side, as well as the need to stretch one end of said frame firstly and then the other end, re-establishing thereafter several times the stretching rate, in one end firstly and then in the other one, in consequence of the high deformation characteristics of the hide. The above method takes consequently a long time and in addition requires a stretching operation to be carried out by hand. Another disadvantage consists in that each frame is to be provided with two stretching mechanisms, which, besides affecting largely the total production costs, can be operated only by hand in the straddling and contraction steps, to be carried out, for each mechanism, successively and not simultaneously. From Italian Patent No. 1,185,292 issued Nov. 4, 1987 of the same applicants, a process and a device are known for stretching individual hides. The device comprises substantially a drawing frame having three strips fitted in end channels, the two outer strips being movable as to the middle strip.
A stretching frame is also provided substantially with two heads with two oppositely movable slides, respectively. The hide to be stretched is fastened, by metal stitches, along its longitudinal edges on the side strips and in the middle of the ends on the middle strip. For stretching the hide, the drawing frame is arranged in the stretching frame, the pins of side strips being fitted in seats provided in the mentioned slides and the pins of the middle strip fitted in seats existing in the fixed parts of the heads of the stretching frame. The separating movement of the side strips is effected by means of a cylinder-piston assembly connected to the slides, whereby the hide is stretched. Although said method and device provided a flawless stretching of the hide, which can be carried out quickly and with the desired stretching rate depending on the type of the hide to be stretched, it has been found that said method and device can be further improved.